Method of backing up electrotype-shells in the manufacture of electro-type-plates.



l G.B.DUNT0N. l METHOD 0F BACKING UP ELEGTROTYPE SHELLS IN THB MANUFAGTURB OF ELBGTRTYPB PLATES.

APPLICATION FILED JUNE 24, 1911.

1,073,105, Patented sept. 16,1913.

WITNESSES ENTOR UNITED sTATEs PATENT onirica.

GEORGE E. DUNTON, OF NEW' YORK, N. Y.

METEO-D 0F BACKING UP ELECTROTYPE-SHLLS IN' THE `MANUFACTURE 0F ELEGTBO TYPE-PLATES,

Specification o! Letters Patent.

Application Med June 24, 1911. Serial No. 635,195.-

Patented sept. 1c, 191e.

' tion, such as will enable others skilled in the art to which it pertains to make and use. the

same. Y i

My invention relates to an improved method of backing up electrotype shells in 4the manufacture of electrotype plates.

It has for its object the uniting of metals, or other materials, having dilferent melting points into a composite body, particularly to form a backing on a printing shell.

The invention consists in taking a metal, whichhas been previously formed in the shape of a printing shell, vand placing it in an open receptacle, preferably a backing pan, treating the back of the shell with a binding substance, heating the open receptacle, shell and the binding substance thereon, closing and sealing the receptacle, heating the closed receptacle and shell and finally forcing the moltenmetal which is to form the' backing of the shell, into the closed receptacle under continuous pressure so that all the molten metal necessary to completely fill all the indentures or interstices formed in the shell, by the letters or other characters, will be forced in before any of the molten metal becomes set and then allow the shell and its backing to set and cool, while still under pressure, thus causing the bucking to be firmly united to the shell and form therewith a composite body.

The metal above referred to, which is formed in the shape of a printing shell, is made preferably of copper but may be made of nickel, steel, brass or vany other suitable metal having a melting `point higher than the metall with which it is to be combined or joined to form a backing therefor. The

other metal above referred to, which is to' be joined to the back of a `printing shell and form a backing therefor, is composed preferably of acombination of lead, tin and antimony inabout the following proportions: lead,'96 per cent.; tin, 2 per cent. and antimony, 2 per cent.y

The melting point of electrolytic copper, of which the printing shell is made, is about 2550 degrees Fahrenheit, the melting point of. the solder or binder which is applied to sald shell, is about 530 degrees Fahrenheit and the metal which is united to said copper shell through the medium of the melted binder and forms a backing for said shell attains a molten state at about 625 degrees Fahrenheit. f i

In 'the drawings, which illustrate one form of apparatus for carrying out my method z-Figure l is alsectional view of the receptacle or backing pan and printing shell with the binder applied. Fig. 2 is a side elevation of the receptacle or backing pan with the cover thereon locked and sealed,

the backing pan, printing shell, binder and nolten metal backing being shown in dotted ines.

Referring to the drawings in which like reference characters denote 'like parts throughout the several views, 1 represents the receptacleor backing pan adapted to be mounted on set screws 2, to provide means for leveling the same, and 3 is the cover which when applied to the receptacle and locked thereon forms a sealed closure. The means for locking and sealing the cover to the receptacle or backing pan consists of pivoted clamps 4. The molten metal backing is introduced into the sealed closure by means of a nipple or short pipe 5, one end of which is inserted into an orifice 6, formed in the cover and receptacle, and the opposite end connected to a suitable pump situated on or in the melting pot of a furnace; The printing shell is represented ut 7, the solder or binder at 8 and the molten metal backing at 9.

Ordinarily in uniting or joining one inet-al to another, in a cold state, it is pos-` sible to place tin or solder foil between the two surfaces to be joined, bind the metals together, apply pressure and heat both until the tin or solder foil melts and adheres to the surfaces of both metals and binds the said metals together and upon becoming cooled to the temperature of the surrounding atmosphere, said metals are hermetically joined one to the other.

In the backing up of Aan electrotype shell, which comprises the joining of the backing metal to the electro-type shell, it is impossible to proceed as above described as the vshell is very delicate as it varies in thickness from one one thousandth to five one thousandths of an inch and the surface is uneven, caused by numerousindentures or interstices in its back which conform to the general contour of its face or surface, in reverse, and if suflicient pressure were applied to insure the forcing of the solder or other binding substance together with the metal comprising the backing, in acold or rigid state, into the indenturcs or interstices, the elevated port-ions or projections, formin the back of the electrotype shell, would be forced into the face of the shell and crush itandA the entire shell would be ruined. It will also -be seen that in order to have the types and other printing surfaces withstand the pressure which .it is :necessary to apply to the electrotype plate during the process of printing, which sometimes calls for hundreds of thousands of impressions from the surface of a printing plate, the backing must fill up all the recesses in the back of the shell, which are behind or underneath the faces of the letters or other printing' surfaces, and be made to conform to the General contour of the face of the shell along the line of junction at the back, without crushing in the elevations on the back, which are the spaces between the types on the printing surface whichjs the face of the electrotype plate. The final surface of the back wlnch has been joined to the electrotype shell must have an even, flat, perfectly level surface, and all parts be in a plane perfectly parallel to that of the printing surface of the electrotype plate.

In the practice of my method, I first produce the metallic electrotype shell, which may be made of copper, steel, nickel or other suitable material, in the usual manner, by the electrodeposition of the desired metal upon the conductive surface of a prepared wax mold, although a mold of lead or other suitable material would serve the same purpose, and having secured the desired thickness for the shell,'I remove the shell from the surface ofthe wax mold by pouring boiling hot water over the surface of the shell which heats the metal and breaks the adhesion between the wax Aof the mold and the metal of the shell, when the shell can be 4easily stripped o and pulled away from the mold, then I rinse the shellin boiling hot lye, to remove all traces of wax which f may have adhered thereto, and then (plunge flux solution, composed of ammoniated muriate of zinc dissolved in Water, by washing the back surface Well with said solution and allowing the surplus liquid to drain ofi", then place the shell, treated as above described, 1n the open receptacle, or backing pan, and apply the soldering foil or cement binder over the back surface of the shell and cause said soldering foil or binder to adhere i the said treated surface on the back of the shell by subjecting the open receptacle and the shell therein to a degree of heat sufficient, or more than suicient, to 'melt the solderingfoil or binder and cause it to run into all, the indentures or interstices in the back surface of the shell and completely covei` -said back-surface. The said Open receptacle and the shell therein are heated, preferably,'by placing the receptacle` in the melting ot containing molten metal and allowing 1t to float on the surface of the said molten metal until the shell becomes heated to the desired degree, after which the receptacle and shell are removed from the melting pot and placed on a suitable stand. The cover which has been previously heated in any desired manner, is then applied to the receptacle and clamped and sealed thereon by means of suitable clamps and thereby, in combination with the receptacle or backing pan forms a closure, molten metal, which is to vform the backin forced through the nipple or short pipe by a pump or other means into the interior of the closure and over the back surface of the shell, which as before stated has beenpreviously treated with a soldering Eux solution and soldering toil and heated, and said molten metal iills all of the interstices or indentations in said shell and also completely fills the closure, then the closure and its contents are cooled, by any suitable means, and allowed to set and thus Jform a composite body after which the shell with the backing firmly united therewith and forming a printing plate is sawed into the desired sizes and finished in the usual well known manner to lit it for use in printing.

As the metal cools, it will contract or shrink and to compensate for such contracting or shrinkage the pressure by the pump on the molten metal is constantly maintained, which causes the molten metal to continuously flow into the closure and ll up vany s ace caused by .contraction or shrinkage efore the metal has set and keeps the closure full-at all times.

1. The method of forming a composite body, consisting in taking two metals one of which is in the shape of a printing shell and melts at a `high temperature and the other to form the backing for the shell and melting at a low tem erature, applying a binder to the shell, p acing the shell in a receptacle, forming a'closure by applying 95 forthe shell, is then a cover to the receptacle, maintaining a substantially constant air tight closure while the cover. is in place, heating the closure and the shell therein until the binder melts, introducing molten metal into the closure and causing it to ll the closure and the interstices in the shell and breaking the substantially air tight closure by removing the cover, substantially as descrlbed.

2. The method of forming a composite body, consisting in taking two metals one of which is in the shape of a printing shell and melts at a high temperature and the other to form the backing for the shell and melting at a low temperature, applying a binder to the shell, placing the' shell in a receptaele, forming a closure by applying an air tight cover to the receptacle, maintainingV a substantially air tight closure while the cover is in place, heating the closure and the shell therein until the binder melts, introducing molten metal into the closure and causing it to fill the closure and the interstices in the shell and breaking the s ubstantially air tight closure by removing the cover, substantially as described.

In testimony whereof, I aiix my signature in the presence of two witnesses.

' GEORGE E. DUNT ON. Witnesses:

\ FRANCIS S. DUFF,

H. BECKER. 

